Tire deflation indicator



Aug. 24, 1937.

Filed Feb. 5, 1955 GUM Patented Aug. 24, 1937 UNITED STATES PATENT .OFFICE 2 Claims.

The invention relates to deflation indicators for pneumatic tires and hasv as an object a device that will indicate by either visual or audible signals when a tire becomes deflated either partially or totally.

It is a further object of the invention to provide a device which may be utilized either upon a motor driven vehicle or a trailer driven thereby for the purpose referred to.

'It is a further object of the invention to provide a device of the character referred to which will be simple and cheap to manufacture, as well as efiective in use.

Further objects of the invention will appear from the following description when read in connection with the accompanying drawing showing illustrative embodiments of the invention, and wherein:

Figure l is a side view of the device applied to a vehicle;

Fig. 2 is a plan view of a vehicle frame with the body omitted, showing the device applied thereto;

Fig. 3 is a detail side elevation of the device in indicating position;

Fig. 4 is a vertical section on line 4-4 of Fig.

'3; and

Fig. 5 is a side view of a difierent form of the invention.

It is sometimes difiicult to detect a flat tire, particularly on the rear wheels of a vehicle and in the case of a trailer there is no indication to the driver of the vehicle hauling the trailer when a tire becomes deflated except sound of the rim bumping upon the pavement, which sound is usually drowned by noise of the vehicle itself.

The present invention is applicable to a trailer and has provisions of means for indicating such deflation, which means may be mounted upon the dash oi. the vehicle to which the trailer may be attached.

The invention as shown in Figures 1 and 2 is applied to a four-wheel vehicle, which may be a motor vehicle or a trailer, but it is obvious that the device may be applied in the same manner to a two-wheel trailer. Preferably one of the devices, as i0, is applied to each side of the vehicle upon which a flat tire is to be indicated. As shown, the device comprises a vertical plate H which may be attached to the sill l2 of the chassis, as by means of a rivet i3. Upon the lower end of the plate ii there is shown pivoted a T- shaped plate H having a horizontal member i5 and a vertical member it, which latter member, as shown in Figure 1, is positioned to'clear the ground or pavement when the tires are fully inflated.

To keep the vertical member IS in vertical position, the ends of the member 5 are shown as connected by means of tension springs i1, iii to the ends of a second horizontal member l9, which latter member may be secured to the plate I i and the sill l2 by the rivet l3, and also by means of a rivet 20 passing through the chassis member 2| as shown in Figure 4. The two rivets l3 and 20 will prevent rotation of the member i9.-

To indicate the contact of the end of member IS with the ground which will swing the member I4 to the position shown in Figure 3 as the vehicle moves, there are shown cables 22, 23 each secured at a point midway of the width of the vehicle to a cable 24, which may be connected about pulley 25 and attached to an indicating device 26, Figure 1, the cable 24 being kept taut by means of a tension spring 21 upon the dash of the vehicle.

The indicating device is shown as comprising the said spring 21, a sliding rod 28 to which the spring 21 is connected and a pointer 29 moving over a scale 30 whereby pull upon the cable 24 caused by deflection of the member H by contact with the ground will immediately be shown upon the scale 30.

Instead of the visual signal described,- an audible signal may be actuated by means of an arm pivoted upon rivet 20 at 34 and held in normal position by spring 35 acting in compression to hold contacts 36, 3! separated as shown in Figure 1. An end of the arm 33 is shown as connected to member i5 by means of a tension spring 38, which when tensed by movement of the member i5 overcomes compression spring 35 to bring the contacts together and to close the circuit through an audible signal, as a bell 39.

The bell 39 may be placed as shownin Figure 1 adjacent the device III or at any other place upon the vehicle, either the trailer or the motor vehicle, as will be obvious, and a battery 40 may be the battery provided for ignition and lighting the vehicle.

In the form of the invention illustrated in Figure 5, the actuating member i6 is shown as a single straight bar pivoted between its ends upon the member H which in turn is shown as rigidly secured to the sill 12. The member I6 is shown as provided with an eye 42 above its pivot to which the cable 22' may be secured to be passed about pulleys 43 and 44 and secured to spring 21. It will be seen that movement of member IS in either direction about its pivot will cause movement of indicator 29' and that the spring 21' will act to hold the member It in normal position when out of contact with the pavement. Contacts 36' and 31' may be applied to this form of the device. In case the audible 5 signal only is desired for use with this form of the device, the spring 21' may be transferred to the member II with one end secured directly to eye 42 and the upper end anchored upon member H. w The device in may be so placed as to be actuated only when a tire is substantially fiat, or it -may be so placed to have the member 55 contact the ground so as to actuate a signal as soon as a tire becomes too soft. Obviously both 15 forms of signal may be utilized atthe same time. Desirably the end of the member it is provided with a roller 4| for an obvious purpose, although such provision is not essential.

Minor changes may be made in the physical 20 embodiments of the invention without departing from the spirit thereof within the scope of the appended claims.

I claim: a 1. A device 01' the class described comprising, 25 in combination: a support to be secured to the frame of a pneumatic tired vehicle; a 'T-member pivoted upon said support with a leg normally positioned out of contact with the pavement; tension springs connected to the head of said 30 member upon opposite sides of said pivot, the opposite ends of said springs anchored upon said support whereby to hold the first named leg in aceaior central position; a cable connected to one branch of said head and passing to an indicating device adjacent a driver's position; spring means to hold said cable taut; and indicating means to show the amount of yielding of said last named spring means upon movement of said device caused by contact with the pavement.

2. A device of the class described comprising, in combination: a support to be rigidly secured to the frame of a pneumatic tired vehicle, comprising a plate to extend downwardly from said frame and a transverse member secured adjacent its central portion to said plate near its upper end; a T-member pivoted at the central portion of its head to the lower portion of said plate with the arms of said head normally mrallel with said transverse member; the effective combined length of said plate extension and the vertical leg of said T-member being such as to space the lower end of the latter from the pavement less than the cross-sectional diameter of an in.- fiated tire of the vehicle; balanced tension springs anchored to the opposite ends of said transverse and T members; fixed and movable electrical contacts carried by said support; a spring holding said contacts normally open; and a spring of greater stifiness than the last named spring anchored to the movable. contact and to an arm of said T-member to close said contacts when the leg of said T-member contacts with the ground while the vehicle is in motion.

WILLIAM Z. MOSS. 

